[s3e11] The Maternal Congruence Today

: Leonard is terrified that his mother will disapprove of Penny, whom Sheldon describes as having a career defined mostly by memorizing the Cheesecake Factory menu.

: In the opening scene, the gang is watching the 1966 How the Grinch Stole Christmas! . Funnily enough, guest star Christine Baranski also appeared in the 2000 live-action film adaptation. [S3E11] The Maternal Congruence

: Sheldon jokes about leaving the Enterprise in a shuttlecraft to a planet he rules, "Sheldon Alpha 5," a nod to the planet Ceti Alpha 5 from Star Trek II: The Wrath of Khan . Critical Reception : Leonard is terrified that his mother will

: In a drunken state, Beverly returns to the apartment and unexpectedly kisses Sheldon on the lips before deciding she'd actually rather "have the busboy" from the bar. Trivia & Highlights Funnily enough, guest star Christine Baranski also appeared

As Leonard and Penny prepare for Christmas, Leonard fails to mention that his brilliant yet emotionally distant mother is coming to town. When Beverly arrives, the tension quickly mounts:

: This episode is notable for being the first of only two in the series where a main character— Raj Koothrappali —appears but has no speaking lines .